What's the best way to measure distance (most accurate), gps or laser or hand held measuring wheel?

Question

Measuring Distance

Answer 1

laser.  Gps (depending on type) generally are accurate to within a few feet.  Measuring wheels depend on the person reading them to guide them in a straight line between point a and b and rotation of the handle when you set it down relative to when you take the measurement.

Answer 2

The answer unfortunately is that it depends upon what you are measuring and how well you use them. For instance, the GPS will not accurately measure the actual distance you must travel over hills. The laser system while perhaps accurate to nanometers, is limited to line-of-sight approximations. The odometer on your car (a measuring wheel essentially) can be very accurate in measuring actual road distance, but is inaccurate when determining actual geo-coordinates without a lot of work.